What you see with the build working not the notebook not coming up is the classic outcome when you try to use the strongly discouraged Dockerfile route and don’t strictly follow the steps detailed here.
Fortunately, the steps executed via the Dockerfile are all easily accomplished using the abilities available in the standard configuration files recommended for use with MyBinder launches.
I forked your repo and made a version using standard configuration files.
Try it out by clicking here to launch and then opening the ’ ACT_Conveyance_Duty.ipynb’ notebook and running it.
You’ll see it works now with the only oddness being a warning about included file "count.mzn" overrides a global constraint file from the standard library. This is deprecated. Importantly, the basics are working now in sessions served by MyBinder.org without need for a Dockerfile.
Fork is here.
If you look around in it, you’ll see everything I changed is put in a binder directory. The MyBinder service will use configuration files in such a directory preferentially, and so it allows leaving your Dockerfile in root alone. I thought maybe that Dockerfile works for you somewhere. I copied yours into binder to modify it; however, I soon abandoned tinkering with it as I figured it looks simple enough to do by supported methods. It still is in there renamed as so not to interfere.
One choice I made was to go with using a current version of minizinc built from source using postBuilt. I was having trouble getting what I think is an old version that is at apt-get to work as your code seemed to expect. Maybe it isn’t as old as I think? Copyright indicated it may date to 2018 unless updating that part of the code was an oversight. Anyway, that may be a further option to adjust if you want. It does add significant time when it has to build the image.
Another place that could use further addressing is what I did to get optimathsat to work. I sort of tried a few things and left the code cluttered. As it is now in postBuild, adjusting anything there results in running compiling from source and so it is not directly convenient to play around unless I remove the compiling for some time.
Also I tried to add gecode before compiling so I could set -DGECODE_ROOT=; however, I haven’t tested that actually worked.